Cant find package from $GOROOT and $GOPATH

Question

Small part of error I'm getting after trying to run go build command

go build ./...
trillian.pb.go:7:8: cannot find package "github.com/golang/protobuf/proto" in any of:
    /usr/local/go/src/github.com/golang/protobuf/proto (from $GOROOT)
    /Projects/Proj1/trillian/src/github.com/golang/protobuf/proto (from $GOPATH)

trillian.pb.go:11:8: cannot find package "github.com/golang/protobuf/ptypes/any" in any of:
    /usr/local/go/src/github.com/golang/protobuf/ptypes/any (from $GOROOT)
    /Projects/Proj1/trillian/src/github.com/golang/protobuf/ptypes/any (from $GOPATH)

trillian_admin_api.pb.go:12:8: cannot find package "github.com/golang/protobuf/ptypes/empty" in any of:
    /usr/local/go/src/github.com/golang/protobuf/ptypes/empty (from $GOROOT)
    /Projects/Proj1/trillian/src/github.com/golang/protobuf/ptypes/empty (from $GOPATH)

trillian.pb.go:10:8: cannot find package "github.com/google/trillian/crypto/sigpb" in any of:
    /usr/local/go/src/github.com/google/trillian/crypto/sigpb (from $GOROOT)
    /Projects/Proj1/trillian/src/github.com/google/trillian/crypto/sigpb (from $GOPATH)

trillian_admin_api.pb.gw.go:17:2: cannot find package "github.com/grpc-ecosystem/grpc-gateway/runtime" in any of:
    /usr/local/go/src/github.com/grpc-ecosystem/grpc-gateway/runtime (from  $GOROOT)
    /Projects/Proj1/trillian/src/github.com/grpc-ecosystem/grpc-gateway/runtime (from $GOPATH)

trillian_admin_api.pb.gw.go:18:2: cannot find package "github.com/grpc-ecosystem/grpc-gateway/utilities" in any of:
    /usr/local/go/src/github.com/grpc-ecosystem/grpc-gateway/utilities (from $GOROOT)
    /Projects/Proj1/trillian/src/github.com/grpc-ecosystem/grpc-gateway/utilities (from $GOPATH)

trillian_admin_api.pb.go:15:2: cannot find package "golang.org/x/net/context" in any of:
    /usr/local/go/src/golang.org/x/net/context (from $GOROOT)
    /Projects/Proj1/trillian/src/golang.org/x/net/context (from $GOPATH)

trillian_admin_api.pb.go:10:8: cannot find package "google.golang.org/genproto/googleapis/api/annotations" in any of:
    /usr/local/go/src/google.golang.org/genproto/googleapis/api/annotations (from $GOROOT)
    /Projects/Proj1/trillian/src/google.golang.org/genproto/googleapis/api/annotations (from $GOPATH)

trillian_log_api.pb.go:65:8: cannot find package "google.golang.org/genproto/googleapis/rpc/status" in any of:
    /usr/local/go/src/google.golang.org/genproto/googleapis/rpc/status (from $GOROOT)
    /Projects/Proj1/trillian/src/google.golang.org/genproto/googleapis/rpc/status (from $GOPATH)

trillian_admin_api.pb.go:11:8: cannot find package "google.golang.org/genproto/protobuf/field_mask" in any of:
    /usr/local/go/src/google.golang.org/genproto/protobuf/field_mask (from $GOROOT)
    /Projects/Proj1/trillian/src/google.golang.org/genproto/protobuf/field_mask (from $GOPATH)

Go env output

GOARCH="amd64"
GOBIN=""
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/Projects/Proj1/trillian"
GORACE=""
GOROOT="/usr/local/go"
GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64"
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build690359699=/tmp/go-build -gno-record-gcc-switches"
CXX="g++"
CGO_ENABLED="1"

GOPATH and GOROOT are set but still can't run the command without errors. Tried installing to home and custom directories changing gopath and goroot regardless but still no luck. Any suggestions how to solve this?

Answer 1

All the packages imported are looked in under GOROOT and GOPATH environment variables first. Make sure your package is somewhere under these directories.

Now Suppose GOPATH is set to : /Users/test/Desktop/GoProject

and GOROOT : /usr/local/go (where go is installed) . If a file in your GoProject has a package imported as

import "abc/def/packageName"

then it should be present at any of the below two places:

/Users/test/Desktop/GoProject/src/abc/def/packageName/* /usr/local/go/src/abc/def/packageName/*

If not, you will get error as reported in the question.

The files inside these directories will have the first line as

package packageName

stating that all these files constitutes a package packageName

Answer 2

As the official document says:

The simplest way is to run go get -u github.com/golang/protobuf/{proto,protoc-gen-go}.

See full introduction here :golang/protobuf installation.